It's an interesting question. I'm a heavy NEX user who's invested in the system not so much financially (I own only 2 E lenses as I find the line-up really poor and lousy as a whole), as emotionally. I totally bonded with the NEX 7 and find the 6 (that I also own) a solid performer, and the menus and peculiar interface have become totally intuitive to me at this point (especially on the 7, whose TriNavi system is genius imo).

To me the only real question is : do you need AF. It all boils down to that. I just ordered a Lens Turbo focal reducer which is going to let me use Nikon FF lenses at their native focal lentgh and aperture (please don't going into hair splitting, I know it's a rough equivalence, but good enough for me). I am comfortable with the loss of AF (many of those lenses I use don't have AF in the first place). I resent the fact that it ties me to a single mount (or could get awfully expensive if I wanted several of those adapters in various mounts), but I think I can also live with that. If an OM to NEX Lens Turbo is born in the future, I might consider this and stick to OM lenses. Or maybe by then I'll have my need covered in Nikon AI-s and F lenses, doesn't matter.

So really the answer to that question is more about global systems than camera bodies (as always, anyway). I personally want 3 lenses : a "normal" (50mm equivalent) prime, a standard zoom (28-70 equivalent, fast aperture) and a fastish tele (70-200 at F4 max is good). And I can live without AF so far. However, I realise many people have totally different needs, want a much larger lens selection, and will not do without AF (which shouldn't be a problem much longer as I think all manufacturers are working really hard at craking the mirrorless AF riddle).

At this point I wouldn't switch my NEX 7 for anything else than a NEX 7 replacement with *much* faster AF and a touch screen (if neither, no us upgrading at all for me). YMMV.